The .rar extension indicates this is a compressed archive file. You will need software like WinRAR or 7-Zip to extract the game files.
This file is generally associated with a fan-made, retro-style action-arcade game titled "Whackerball," often described as a fast-paced "whack-a-mole" style game mixed with air hockey or breakout mechanics. Whackerball.rar
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